const arr1:[number,boolean] = [1,false]
arr1.push(2,3,4)
console.log(arr1)
const arr2:readonly[x:number,y?:boolean] = [1,true]
// arr2.push(1)//只读
console.log(arr2)

let excel:[string,string,number][]=[
    ['wyx','zs',18],
    ['wyx','zs',18],
    ['wyx','zs',18],
    ['wyx','zs',18]
]
console.log(excel)

type first = typeof arr1['length']